The Green Party says the extra cost of recent changes to the Emissions Trading Scheme contradicts what the Government promised before last year's election.
Earlier this month, Climate Change Minister Tim Groser announced changes to the scheme that will cost an estimated $328 million over the next three years.
Greens' co-leader Russel Norman says that breaches a National Party promise to keep any changes to the scheme fiscally neutral.
Dr Norman says the move gives a clear indication of where the Government's climate change policy is heading.
"The Government's delivering zero budgets and yet they have managed to find an extra $82 million a year in order to subsidise pollution, clearly their priorities are to support polluters and to trash the environment".
Tim Groser is travelling overseas and could not be reached for comment.